Generally, in power line communication (PLC) or power line carrier communication, there is bidirectional communication by means of a handshaking method between the main unit and a sub-unit, where the main unit verifies data received from the sub-unit without fail and communication is determined to have been successful when the main unit accepts the data.
A prior disclosed example of lighting equipment control via power line communication is listed in Japanese Published Unexamined Application No. 2011-234064. In this exceptional prior example, the main unit of control establishes no bidirectional communication with individual sub-units when using a machine (node) capable of power line carrier communication to remotely control a sub-unit installed on a node, by superimposing control signals from a transceiver acting as main unit onto the power line. The main unit transmits commands by constantly sending out only broadcast signals to the grouped sub-units capable of power line communication. Here, it is stated that the unique ID number of each sub-unit is recorded in the power line carrier communication microcomputer.